Screened empirical bond-order potential for Si-C-H

Lars Pastewka (Fraunhofer IWM, Freiburg, Germany)

First nearest-neighbor models are routinely used for atomistic modeling of covalent materials. Neighbors are usually determined by looking for atoms within a fixed interaction range. While these models provide a faithful description of material properties near equilibrium, the limited interaction range introduces problems in heterogeneous environments and when bond-breaking processes are of concern.

I demonstrate that the reliability of reactive bond-order potentials is improved by using an environment-dependent first nearest-neighbor definition. I will discuss general considerations and show specific results obtained using an augmented version of the second generation reactive empirical bond-order potential for C-H and the recent Si-C-H incarnation by Schall and Harrison, as well as results obtained for simple Si-C Tersoff-type potentials.

• Pastewka, Pou, Perez, Gumbsch, Moseler, Phys. Rev. B 78, 161402(R) (2008).
• Pastewka, Mrovec, Moseler, Gumbsch, MRS Bull. 37, 493 (2012).
• Pastewka, Klemenz, Gumbsch, Moseler, Phys. Rev. B 87, 205410 (2013).